Firewall on the ZyXEL Q1000Z

5. Choose whether the firewall rules will apply to All Dynamic IP Addresses or All Static IP Addresses.

6. Select the security level. All three of the Firewall levels or settings can be modified with the
exception of "OFF". When set to "OFF", the firewall still provides protection in the form of NAT and SPI
(Stateful Packet Inspection).

7. Once a security level is selected, you will be given a list of services and ports.
Any box that has a check mark is allowed; any box that is empty is blocked, or disallowed.

The example shown below is a subset for the Medium setting. Selecting Low and High
have the exact same services available to choose from, but each has different default options
selected as a starting point.